1. Field of the Invention
The present invention relates to apparatus for processing image data and a method of selecting image data processing functions via a graphical user interface.
2. Description of the Related Art
Systems for processing image data, having a processing unit, storage devices, a display device and a stylus-like manually operable input device (such as a stylus and touchtablet combination) are shown in U.S. Pat. Nos. 5,892,506; 5,786,824 and 6,269,180 all assigned to the present Assignee. In these aforesaid systems, it is possible to perform many functions upon stored image data in response to an operator manually selecting a function from a function menu.
Recently, in such systems as “Toxic”, “Fire” and “Inferno”, licensed by the present Assignee, the number of functions that may be performed have increased significantly. Thus, for example, there has been a tendency towards providing functions for special effects, compositing and editing on the same platform.
Function selection is often done via graphical user interfaces (GUIs) in which menus are displayed from which a selection may be made. A function selection using a menu is achieved by moving a cursor over to a selection position within the menu by operation of the stylus. The particular function concerned is selected by placing the stylus into pressure; an operation logically similar to a mouse click. Menus of this type are used instead of pull-down menus in systems where stylus-like input devices are preferred, because it is necessary to maintain stylus pressure while menu selection takes place with such pull-down menus. Such an operation places unnecessary strain on the wrists and fingers of an operator and is therefore not preferred in applications that make significant use of stylus-like devices.
The purpose of menus is thus to group functions as function families based upon either their processing functionality (for instance all the functions allowing an image processing user to access and manage image data files, grouped in a “File” menu) or the commonality of data such they process (for instance all the functions allowing an image editor to edit the Red, Green and Blue color component values of image data, grouped in a “Color” menu). Having regard to the stated increasing number of available image processing functions, the situation arises frequently wherein an image processing system user needs to recursively access functions nested in different families, i.e. menus. However, traditional instructions set design, which includes the graphical user interface and menus thereof, requires that image data be re-selected every time a function of a different family is selected, whereby the operational strain problem stated above is compounded by the frequent need to repeat image data selection unnecessarily.
Furthermore, operators and artists are under increasing pressure to increase the rate at which work is finished. Being able to work with systems of this type quickly and efficiently is not facilitated if complex menu structures are provided or manipulation tools are provided that are not intuitive to the way artists work.